Hello there,
I understand that you want to purchase Windows 10 Enterprise 2019 LTSC. You can find information on the requirements and installation guidelines in our Evaluation Center. Also, please check the section, which says, “Buy”.
For more information on Windows 10 Volume Licensing, you can also refer Windows 10 Licensing which provides you the details of Windows 10 Enterprise editions and How to Buy.
You can also contact the Microsoft Licensing Activation Centers worldwide, if you require further assistance.
https://www.microsoft.com/en-us/evalcenter/evaluate-windows-10-enterprise
And see if it helps,
Thank you
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